1. Field of the Invention
An air conditioner and a cooling receiver of the air conditioner and, more particularly, an air conditioner that supercools and stores a liquid refrigerant and a cooling receiver of the air conditioner.
2. Description of the Related Art
An air conditioner is an apparatus for cooling or heating the interior of a room using an air-conditioning cycle including a compressor, an outside (also referred to as outdoor) heat exchanger, an expansion device, and an inside (also referred to as indoor) heat exchanger. The air conditioner may include a cooling unit for cooling the interior of a room and a heating unit for heating the interior of a room. Furthermore, the air conditioner may be a combined cooling and heating air conditioner for cooling or heating the interior of a room.
The combined cooling and heating air conditioner generally includes a cooling/heating switching valve for changing the flow channel of a refrigerant compressed by a compressor depending on a cooling operation and a heating operation. When a cooling operation is performed, the refrigerant compressed by the compressor flows into the outside heat exchanger through the cooling/heating switching valve. The outside heat exchanger functions as a condenser. The refrigerant condensed by the outside heat exchanger is expanded by the expansion device and then flows into the inside heat exchanger. In this case, the inside heat exchanger functions as an evaporator. The refrigerant evaporated by the inside heat exchanger flows into the compressor again through the cooling/heating switching valve.
When a heating operation is performed, the refrigerant compressed by the compressor flows into the inside heat exchanger through the cooling/heating switching valve. The inside heat exchanger functions as a condenser. The refrigerant condensed by the inside heat exchanger is expanded by the expansion device and then flows into the outside heat exchanger. As such, the outside heat exchanger functions as an evaporator. The refrigerant evaporated by the outside heat exchanger flows into the compressor again through the cooling/heating switching valve.
The combined cooling and heating air conditioner may include a plurality of inside units each having an inside heat exchanger may. Only some of the plurality of inside units may operate as a partial load. If only some of connected inside units operate, a refrigerant of a low-pressure gas state is present within the inside heat exchanger of the stopped inside unit. If the refrigerant is sealed by taking into consideration the number of connected inside units, then the refrigerant of an inside unit that does not operate transfers to the outside heat exchanger, which changes a refrigerant circulation state. Accordingly, the optimal amount of a refrigerant may not be distributed to the air-conditioning cycle.
Furthermore, when the heating operation is performed, the functions of the outside heat exchanger and inside heat exchanger of the air conditioner are changed. A ratio of the volumes of the outside heat exchanger and inside heat exchanger is changed depending on the number of connected inside units. Furthermore, it is necessary to control the amount of a refrigerant in response to a change in cooling/heating operation mode.
Accordingly, a receiver in which a refrigerant is stored is installed on the air-conditioning cycle to optimize the amount of the refrigerant of the air-conditioning cycle. The receiver functions to transfer a refrigerant stored therein to the air-conditioning cycle when the amount of the refrigerant of the air-conditioning cycle is insufficient and functions to store the refrigerant of the air-conditioning cycle when the amount of the refrigerant of the air-conditioning cycle is excessive, so the amount of the refrigerant of the air-conditioning cycle becomes an optimal amount. Also, the air conditioner may include a supercooler to supercool a refrigerant that has passed through the outside heat exchanger when the cooling operation is performed. The supercooler, disposed between the outside heat exchanger and the inside heat exchanger, functions as an intercooler.
Recently, complex type air conditioners are being installed in locations, such as supermarkets. More particularly, the complex type air conditioner integrates an air-conditioning cycle circuit for air-conditioning the interior of a room and a refrigeration cycle circuit for refrigerating a low-temperature storage unit (such as a display case for storing food at a low temperature). In the complex type air conditioner, the supercooler supercools a refrigerant that has passed through the condenser of the refrigeration cycle circuit and overheats a refrigerant that has passed through the condenser of the air-conditioning cycle circuit. This is done by thermally exchanging the refrigerant passing through the condenser of the refrigeration cycle circuit and the refrigerant passing through the condenser of the air-conditioning cycle circuit. However, such conventional air conditioners are problematic because installation space is limited. Moreover, because the receiver and the supercooler are separately formed, the structure is complicated and costly due to the configuration of refrigerant pipes for forming the receiver and the supercooler into a cycle circuit, and refrigeration efficiency is low.